Active matrix liquid crystal displays (AMLCDs) are based on the twisted nematic (TN) effect. One drawback of conventional TN LCDs is that optical characteristics such as contrast and color saturation are strongly dependent on the direction of viewing. Because of this drawback, among others, the viewing angle width, i.e., the range of viewing directions, where contrast exceeds a given value may be rather limited.
Conventionally, various technologies have been developed to widen the viewing angle. A wide viewing angle technology which is generally applied in small and medium LCDs uses two individual discotic compensation films which are produced by Fuji Film; the two individual discotic compensation film layers are disposed on opposing sides of an AMLCD element. The discotic compensation films are made of disc like liquid crystal molecules, which are tilted with respect to the film plane. Conventionally, the two compensation films are used between the front polarizer and the front substrate of the liquid crystal display element and between the rear polarizer and the rear substrate of the liquid crystal display element.
This conventional structure may act to improve the field of view; however, it may still be inadequate for certain applications, such as but not limited to micro LCDs, used in near-to-the-eye applications or projection displays. Further, this conventional structure may provide for improved contrast but only in an asymmetric manner over the field of view. For example, good contrast can be achieved only in one direction (typically horizontal direction). In other directions, the high contrast may be possible, but only in a narrow region.
Accordingly, there is a need for display systems utilizing discotic compensation films to improve the viewing angle performance of micro-liquid crystal displays and any other types of liquid crystal displays.
There is also a need for display systems using multiple liquid crystal films positioned on one side of the display element to achieve high contrast ratio in a wide and symmetrical viewing angle.
Further, there is a need for display systems using multiple discotic films on each side of the LCD panel that can further improve the viewing angle in the vertical direction, while maintaining good contrast in the horizontal direction.
It would be desirable to provide a system and/or method that provides one or more of these or other advantageous features. Other features and advantages will be made apparent from the present specification. The teachings disclosed extend to those embodiments which fall within the scope of the appended claims, regardless of whether they accomplish one or more of the aforementioned needs.